Television signal reception method and module

ABSTRACT

According to the invention, in the method of receiving broadcast television signals:
         a main component (C 1 ) is received (E 6 ) in a multimedia receiver terminal (T);   a secondary component (C 2 ) is acquired (E 5 ) in the multimedia receiver terminal (T) via a remote computer network (R), main time stamps (TSFCS 1 ) referenced to a predetermined reference time (TSFCS 10 ) being inserted beforehand into the main component (C 1 ), and secondary time stamps (TSFCS 2 ) referenced to said predetermined reference time (TSFCS 10 ) being inserted into the secondary component (C 2 ) prior to reproduction, the time stamps marking content reproduction advance; and   the received main component (C 1 ) and the acquired secondary component (C 2 ) are reproduced (E 6 ) on the multimedia receiver terminal (T) in compliance with the chronology of the secondary time stamps and the main time stamps, to reproduce for the user a coherent audiovisual content made up both of the main component (C 1 ) and of the secondary component (C 2 ).

RELATED APPLICATIONS

This is a U.S. National Phase Application under 35 USC 371 ofInternational Application PCT/FR2004/002276, filed on 8 Sep. 2004.

FIELD OF THE INVENTION

The invention relates to a method of receiving television signals.

One field of the invention is that of televisions or other apparatus forreceiving television signals and more generally audiovisual content overtelevision channels.

BACKGROUND OF THE INVENTION

Television signals conventionally carry simultaneously the picture andthe soundtrack of the audiovisual content to be reproduced by the user'stelevision.

There is an increasing requirement to expand the audiovisual content onoffer. Thus data that the user can consult on a television may be addedto the picture and soundtrack.

However, the information that is broadcast must be adapted to thenecessarily limited bandwidth of television channels, which restrictsthe volume of information that can be broadcast.

SUMMARY OF THE INVENTION

The invention aims to provide a method of receiving television signalson a multimedia receiver terminal that alleviates the drawbacks of theprior art and expands the possibilities of supplying content to theuser.

To this end, a first aspect of the invention consists in a method ofreceiving broadcast television signals on a multimedia receiverterminal, in which method a main component of the television signalsbroadcast via a first network is received in the multimedia receiverterminal, and which method is characterized in that:

-   -   main time stamps referenced to a predetermined reference time        are inserted beforehand into the main component to mark content        reproduction advance;    -   a secondary component for associating with the main component in        order to reproduce for the user a coherent audiovisual content        made up both of the main component and of the secondary        component is acquired in the multimedia receiver terminal via a        remote second network of computers including a source adapted to        send secondary components, secondary time stamps referenced to        said predetermined reference time being inserted into the        secondary component prior to reproduction in order to mark        content reproduction advance; and    -   the received main component and the acquired secondary component        are reproduced on the multimedia receiver terminal in compliance        with the chronology of the secondary content reproduction        advance time stamps and the main content reproduction advance        time stamps, to reproduce for the user a coherent audiovisual        content made up both of the main component and of the secondary        component.

By means of the invention, the secondary component usually carried bythe television signals containing the main component can be replaced bya secondary component from the second network, which is not thetelevision signal broadcast network. Consequently, the inventioncircumvents the limitations imposed by broadcast television signals onthe secondary component. This capitalizes on the offer of secondarycomponents from the second network, which is potentially much greaterthan the offer from the television signal broadcasting network, and onits ease of access.

Accordingly, if the secondary component is the soundtrack and/orcorresponding subtitles, for example, the subtitles may be viewed on themultimedia receiver terminal in a language other than that imposed bythe television signals, provided that the soundtrack and/or thecorresponding subtitles in that language are available in the secondarycomponent sent to the multimedia receiver terminal via the secondnetwork. Thus the invention opens the way to simultaneous broadcastingby means of television signals of the same content in more than onecountry with different languages, for example in more than one countryin Europe, with the possibility of obtaining in each country thesoundtrack and/or corresponding subtitles in the language of thatcountry.

Synchronizing the main and secondary components enables reproduction onthe multimedia receiver terminal of information that is linked in realtime to the main component, and not merely information that is notlinked in real time to the main component, such as the televisionprogram data that is a feature of DVB signaling.

According to other features of the invention:

-   -   the main content reproduction advance time stamps each have a        main value of the time elapsed since said predetermined        reference time;    -   the secondary content reproduction advance time stamps each have        a secondary value of the time elapsed since said predetermined        reference time; and    -   the presence of a main content reproduction advance time stamp        in the received main component is detected, the acquired        secondary component is searched for a secondary content        reproduction advance time stamp having a secondary value greater        than or equal to the main value of the detected main content        reproduction advance time stamp, and reproduction of the        acquired secondary component is started from the secondary        content reproduction advance time stamp obtained by means of        said search;    -   said predetermined reference time is a published start time of        reproduction of the content of the main component;    -   the main component includes, in addition to said main content        reproduction advance time stamps referenced to said        predetermined reference time, second main time stamps that are        not referenced to said predetermined referenced time and are        respectively associated with said main content reproduction        advance time stamps referenced to said predetermined referenced        time;    -   in the secondary component, the secondary content reproduction        advance time stamps are modified to have the same time reference        as the second main time stamps of the main component by adding        to the secondary content reproduction advance time stamps the        time shift between the main content reproduction advance time        stamps referenced to said predetermined reference time and the        second main time stamps that are not referenced to said        predetermined reference time and are respectively associated        with said main content reproduction advance time stamps; and    -   said reproduction of the received main component and the        acquired secondary component on the multimedia receiver terminal        is effected on the basis of the chronology of the modified        secondary content reproduction advance time stamps of the        secondary component and the second main time stamps of the        received main component, which are not referenced to said        predetermined reference time;    -   the secondary content reproduction advance time stamps are        present from the outset in the secondary component acquired from        the second network in the multimedia receiver terminal;    -   or the secondary content reproduction advance time stamps are        inserted into the secondary component in the multimedia receiver        terminal after acquisition in the multimedia receiver terminal        from the second network;    -   the step of acquiring the secondary component includes storing        the secondary component received from the second network in a        buffer of the multimedia receiver terminal and the step of        reproducing on the multimedia receiver terminal the received        main component and the acquired secondary component includes        extracting the stored secondary component from the buffer;    -   the secondary component is acquired by interrogating an address        of the source of secondary components to be found in description        data present with the main component in the received television        signals followed by downloading from the secondary component        source to the multimedia receiver terminal;    -   or the secondary component is acquired by interrogating an        address of the source of secondary components to be found in        description data present in metadata broadcast independently and        received beforehand by the terminal or consulted beforehand by        the terminal at a known address, followed by downloading from        the secondary component source to the multimedia receiver        terminal;    -   the description data includes for each identifier of a secondary        component the secondary component type selected from at least        audio, subtitle and video, the secondary component language, and        the respective address in the second network at which to obtain        the secondary component;    -   or the secondary component is acquired from the second network        with the aid of a manual search engine and downloaded from the        second network to the multimedia receiver terminal;    -   or the secondary component is acquired by sending it to the        multimedia receiver terminal over the second network in        multicast mode by the secondary component source and storing it        in the buffer;    -   or the secondary component is acquired by downloading it into        the buffer and reading the buffer in streaming mode;    -   the main content reproduction advance time stamps include a main        wanted content interruption time stamp and a main wanted content        resumption time stamp after the main wanted content interruption        time stamp, between which time stamps is a content that is not        wanted in the main component, and which time stamps are        synchronized in the secondary component respectively with a        first secondary wanted content time stamp and a second secondary        wanted content time stamp that is after the secondary wanted        content time stamp, the secondary component between the first        secondary wanted content time stamp and the second secondary        wanted content time stamp corresponding to a wanted content        other than the unwanted content of the main component.

The invention also provides a module for receiving broadcast televisionsignals, for implementing the method as defined above, the moduleincluding means for receiving in a multimedia receiver terminal a maincomponent of television signals broadcast via a first external broadcastnetwork and means for reproducing an audiovisual content for the userbased on the received main component, and the module being characterizedin that it further includes:

-   -   means for acquiring, via the second network of remote computers,        said secondary component that must be associated with the main        component to reproduce for the user a coherent audiovisual        content made up of the main and secondary components; and    -   means for automatically controlling the reproduction means so        that they reproduce the received main component and the acquired        secondary component in compliance with the chronology of the        secondary content reproduction advance time stamps and the main        content reproduction advance time stamps.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention can be better understood after reading the followingdescription, which is given by way of non-limiting example only and withreference to the appended drawings, in which:

FIG. 1 is a diagram of one example of the temporal structure of main andsecondary components according to the invention;

FIG. 2 is a diagram of a first mode of acquisition of a secondarycomponent according to the invention;

FIG. 3 is a diagram of a second mode of acquisition of a secondarycomponent according to the invention;

FIG. 4 is a diagram of a first example of the temporal structure of themain and secondary components in the event of insertion of an unwantedcontent;

FIG. 5 is a diagram of a second example of the temporal structure of themain and secondary components in the event of insertion of an unwantedcontent; and

FIG. 6 is a diagram of another example of the temporal structure of themain and secondary components according to the invention.

DETAILED DESCRIPTION OF THE DRAWINGS

The method of the invention is implemented automatically on a multimediareceiver or multimedia receiver terminal T adapted to receive televisionsignals broadcast by a first source, such as a main broadcaster in FIG.1, via a first network, for example by radio transmission, satellite,cable, or the Internet, and is adapted to reproduce the audiovisualcontent thereof for the user by appropriate means, such as a screen andone or more loudspeakers. For example, the terminal T is either atelevision receiving television signals by radio, satellite, or cable,or a computer or some other terminal receiving television signals viathe Internet. The television signals received by the terminal T includea main component C1 for reproducing a content on the terminal.

The main component C1 carried by the television signals includes main(content reproduction advance) time stamps TSFCS1, as shown in FIG. 1.These main time stamps TSFCS1 are inserted during broadcasting via thefirst network and are therefore present in the main component C1received by the terminal. The main time stamps TSFCS1 are eitherinserted into the component C1 during live broadcasting or are initiallysupplied on a recording medium containing the component C1 if it is notbroadcast live, but instead by reading the recording medium. The maintime stamps TSFCS1 each contain a main time value V1 equal to the timeelapsed (shown in milliseconds in the figures, for example) since a maincontent start time stamp TSFCS10 of the main component C1, for examplesituated at a reference time at the start of a television program suchas a film or other TV broadcast, etc. This main content start time stampTSFCS10 is reset at the start of each content. Between consecutive maintime stamps TSFCS1 there are the associated samples S1 of the maincomponent C1 that represent portions of the component C1 to be viewed onthe terminal T, for example a complete image of the main component C1.The time stamps TSFCS1 indicate the time of reproducing (presenting) theimmediately next sample S1 of the main component C1 coming from theappropriate main decoder (audio, video, subtitle, etc.).

In the FIG. 2 embodiment, the broadcast television signals furthercontain data describing the broadcast content(s), including one or moreaddresses of one or more secondary components C2 present on a remotesource SC and identifiers corresponding to those secondary componentsC2. This remote secondary component source SC is accessed by theterminal via a second data processing network R such as the Internet.

The user can select the main television channel, i.e. the televisionbroadcast channel, during the step E2 using any appropriate means on theterminal T, and hence the main component C1 to be reproduced on theterminal T. This step E2 may be preceded by a step E1 of selecting acontent from a plurality of contents identified in the description dataand broadcast on the various television channels.

In the figures, it is assumed that the secondary component C2 codes thesoundtrack, for example. The secondary component could equally codesubtitles transcribing the soundtrack instead of or in addition to thesoundtrack.

During the next step E3, the user can also select a secondary componentC2 using any appropriate means on the terminal T and its identifier inthe description data associated with the selected main component C1. Thecomponent C1 is the picture and soundtrack in French of a film F1, forexample. The identifiers of secondary components C2 designated in thedescription data D1(F1) associated with that component C1 of the film F1are IDC2 a for the soundtrack of the film F1 in English and IDC2 b forthe soundtrack of the film F1 in German, for example. The descriptiondata includes, for each identifier of a secondary component C2, the type(audio, subtitle or video) TC2 a, TC2 b of the secondary component C2,which is audio in the case of IDC2 a and IDC2 b, the language LC2 a, LC2b of the secondary component C2, which is respectively English andGerman in the case of IDC2 a and IDC2 b, and the respective address ADa,ADb at which the secondary component C2 is obtained on the secondnetwork R, for example.

The selection of a secondary component C2 at the terminal automaticallytriggers the sending of a request in the selected secondary component C2over the second network R during the next step E4 and via a modemincluded in the terminal T; in the preceding example this second networkis assumed to have the identifier IDC2 a and therefore the address ADa.The request is of the http, FTP or other type and is sent to the websiteof the source SC, for example a server. In response to the request, thesource SC sends the corresponding secondary component C2 to the addressADa present in the request. The secondary component C2 is thendownloaded into the terminal or receiver T via the modem during the stepE5. The main component C1 received in the television signals and thedownloaded secondary component C2 are then reproduced on the terminal Tduring the step E6. During this reproduction, the downloaded secondarycomponent C2 is decoded and where appropriate replaces its counterpartin the main channel; in the above example, this means that thesoundtrack in English selected as the secondary component C2 replacesthe soundtrack in French present in the main channel.

Second content reproduction advance time stamps TSFCS2 are inserted intothe secondary component C2 before viewing. In FIG. 1, the secondary timestamps TSFCS2 can be spaced in any manner relative to the main timestamps TSFCS1, for example. The secondary time stamps TSFCS1 eachcontain a secondary time value V2 equal to the elapsed time (inmilliseconds, for example) from a secondary content start time stampTSFCS20 of the secondary component C2 coinciding with the main contentstart time stamp TSFCS10 of the main component C1. Consequently, thesecondary time stamps TSFCS2 have the same time referenceTSFCS20=TSFCS10 as the main time stamps TSFCS1. This secondary contentstart time stamp TSFCS20 is reset at the start of each content. Betweenconsecutive secondary time stamps TSFCS2 there are the samples S2 of thesecondary component C2 which represent the portions of the component C2to be reproduced on the terminal T, for example the soundtrack for thecomponent C2. The time stamps TSFCS2 indicate the time of reproducing(presenting) the immediately next sample S2 of the secondary componentC2 coming from the appropriate secondary decoder.

The samples S1 and S2 in the broadcast component C1 and in the componentC2 present on the second network R together form a coherent audiovisualcontent for the user when reproduced simultaneously on the terminal T.In the previous example, that content consists of a picture and asoundtrack in English that are synchronized, including speech and thelip movements of speakers.

The time stamps TSFCS1 and TSFCS2 may be provided in addition topresentation time stamps (PTS) in the components C1 and C2 in the caseof MPEG-2 TS streaming, but are not systematically reset on each changeof content and may further be subject to changes of reference and todelays in the event of remultiplexing of television channels in thetelevision signal broadcasting network. These time stamps PTS are knownin the art and are shown darker than the time stamps TSFCS1 in FIGS. 1,4, 5 and 6, with their values in milliseconds 19920, 20000, 20040,20080, 20120 indicated underneath by an arrow in FIGS. 1 and 6. Thus fortwo time stamps TSFCS1 and TSFCS2 having the same reference, the timestamps PTS are not guaranteed to have the same reference, which meansthat synchronization using only the time stamps PTS would not functioncorrectly and would give rise to uncontrollable time shifts between C1and C2 that would be perceptible to the user.

The source SC inserts the secondary time stamps TSFCS2 into thesecondary component C2 at source before acquisition from the secondnetwork R or on reception in the terminal T after acquisition from thesecond network.

Where appropriate, the terminal T includes one or more buffers forstoring the secondary component C2 received from the second network Rand extracting it therefrom for reproduction.

At the time of reproducing the components C1 and C2 on the terminal T,the secondary time stamps TSFCS2 are automatically synchronized to thecorresponding main time stamps TSFCS1 by appropriate means in theterminal T, as described below in the case of a first embodiment.

When a sample S1 of the main component C1 is sent to the main decoderfor reproduction, the value V1 of the main time stamp TSFCS1 associatedwith that main sample S1 indicates to the main decoder the time that haselapsed since the reference time TSFCS10 of that main component C1. Ifthe main decoder has begun decoding before the reference time TSFCS10,the elapsed time corresponds to the start of coding of the currentcontent associated with that reference time TSFCS10.

A main detector in the terminal T detects the last content reproductionadvance time stamp TSFCS1 in the received main component C1 and its maintime value V1 is extracted from the detected main time stamp TSFCS1.

Appropriate selection means then automatically search the acquiredsecondary component C2 for the secondary time stamp TSFCS2 having itssecondary value V2 greater than or equal to (for example identical to orimmediately greater than) the detected main value V1 sent to theselection means, and the secondary time value V2 is extracted from thesecondary time stamp TSFCS2 found in this way.

Then, using a local clock of the terminal T, for example, by which themain decoder and the secondary decoder are set, the secondary decoderstarts reproduction of the acquired secondary component C2 at thesecondary sample S2 corresponding to the secondary time stamp TSFCS2that has been found at the reproduction time corresponding to thesecondary time value V2. The main time stamp TSFCS1 and the secondarystamp TSFCS2 are monitored continuously so that the associated samplesS1 and S2 are decoded at the correct time relative to the same starttime stamp TSFCS10.

The above embodiment is shown by way of example in FIG. 1, in which thenumerical values indicated in C1 and C2 are those in milliseconds of V1and V2 for the time stamps TSFCS1 and TSFCS2. If the main decoderdetects in the sample S1 the time stamp TSFCS1 for which V1=80milliseconds (ms), it searches C2 for the secondary time stamp TSFCS2having the lowest value V2 greater than or equal to 80 ms. In this case,the secondary time stamp TSFCS2 for which V2=110 ms will be found in C2.There is a delay of calculated duration DC=V2−V1−DT=110 ms−80 ms−2 ms=28ms from the time V1+DT before triggering reproduction of the sample S2after TSFCS2 by the secondary decoder, which reproduction will thereforebe effected at the time V2, where DT=2 ms is the processing time thathas elapsed since sending the sample S1 to the main decoder, whichdepends on the sending means that were used for this. In FIG. 1, thisreproduction of the sample S2 on the terminal T corresponds to the endof the sample S1 for which V1=80 ms and to the start of the sample S12following the sample Si for which V1=120 ms.

Where appropriate, reproduction on the terminal T of the components C1and C2 during the step E6 is automatically delayed pending the start ofreception by the terminal T of the television signals including theselected main component C1 associated with the downloaded secondarycomponent C2 (i.e. detection of the start main time stamp TSFCS10),which secondary component C2 is stored in the buffer in the meantime.

The terminal T may miss the first samples S1 and S2, i.e. the firstsamples after TSFCS10 and TSFCS20. This does not prevent desynchronizingthe components C1 and C2 to the decoding process, since decoding iseffected under the control of the local clock, which is internal to theterminal T and is locked to the time stamps TSFCS1 of the maincomponent. If the secondary component C2 is downloaded after the startof the selected main component C1, then C1 and C2 are viewed from thedetected current main time stamp TSFCS1 of the main component C1.

Alternatively, the description data containing the address of thesecondary component source SC is present in metadata broadcastindependently and received beforehand by the terminal T or consultedbeforehand by the terminal T at a known address.

In FIG. 3, which is a variant of FIG. 2, no description data is sent toor received by the terminal T, the description data does not contain anyindications of secondary components C2 available on the network R or thecomponents C2 available in the description data do not suit the user. Inthis case, the user is offered manual searching of the second network Rfor the required secondary component C2 in the step E11, using a searchengine present in the terminal T or a television gateway. If the userfinds and selects the required secondary component C2 during the stepE12, the user commands the sending of a request for acquisition thereofin the step E13, which is analogous to the step E4 in FIG. 2, and itsdownloading to the terminal T follows in the step E14, which isanalogous to the step E5 in FIG. 2.

The main television channel is then selected in the step E15, which isanalogous to the step E2 in FIG. 2. During the next step E16, theselected main component C1 of the television signals is received by theterminal T and the main component C1 and the downloaded secondarycomponent C2 are reproduced on the terminal T in a similar manner to thestep E6 in FIG. 2.

As an alternative to FIGS. 2 and 3, acquisition of all the secondarycomponents C2 that can be associated with the selected main component C1is triggered by accessing all the secondary components C2 declared inthe description data and/or searching the second network R for all thesecondary components C2 linked to a particular main component.

As an alternative to FIG. 2, at the time of its reproduction, thesecondary component C2 is read as it passes through the buffer in theterminal T, i.e. in streaming mode, at the same time as portions of thecomponent C2 that are ahead of the read component in time are stored inthe buffer. In this case, the request to the source SC is of the RTSPtype with the URL address of the required secondary component C2 and thecurrent secondary time stamp TSFCS2 that reproduction on the terminal Thas reached. In this case, the source SC is able to send the secondarycomponent C2 from any time indicated in the request (secondary timestamp), to enable the terminal T to ready itself to receive a content atany time. The source SC is able to retime the secondary component thatit sends, at the request of the terminal T, if the transit delay of thenetwork R is too great to enable synchronized decoding with no risk ofinterruption. If the secondary component C2 received at the terminal Tis ahead of time, the samples S2 are stored in the buffer to await thecorresponding samples S1 of the main component C1. If the secondarycomponent C2 received at the terminal T is delayed, the terminal sends arequest to the source SC to command a forward skip in the streaming modereading of the samples S2 to catch up with the corresponding samples S1of the main component C1.

In another variant, the secondary component C2 is acquired by the sourceSC sending it to the terminal over the second network R in multicastmode. In this case, the request to the source SC is of the IGMP type.The secondary component C2 is broadcast by the source SC over thenetwork R at a particular time in advance of the start of the maincomponent C1. The secondary component C2 received is consequently storedin the buffer to wait for the corresponding samples S1 of the maincomponent C1 to be reproduced synchronously with it.

In a second embodiment shown in FIG. 6, which is a variant of the firstembodiment shown in FIG. 1, the main component C1 also includes thesecond main presentation time stamps PTS1 cited above that are notreferenced to the reference time TSFCS10 to which the contentreproduction advance stamps TSFCS1 are linked. These second mainpresentation time stamps PTS1 are also associated with each main sampleS1 and are provided after each main time stamp TSFCS1, for example.

As in FIGS. 4 and 5, in the same way, the aforementioned secondsecondary presentation time stamps PTS2 that are not referenced to thereference time TSFCS20 to which the content reproduction advancesecondary time stamps TSFCS2 are referenced are associated with thesecondary time stamps TSFCS2, for example follow each of them. Thesesecond secondary time stamps PTS2 have any reference time relative tothe stamps PTS1 and generally have a reference time different from thatof the stamps PTS1.

In FIG. 6, the content reproduction advance secondary time stamps TSFCS2are modified in the secondary component C2 to give them the samereference time as the second main time stamps PTS1.

To this end, the respective time values of the second main time stampsPTS1 are added to the value V2 of the content reproduction advancesecondary time stamps TSFCS2 of C2 and the respective time values V1 ofthe content reproduction advance main time stamps TSFCS1 associated withthe second main time stamps PTS1 in the main component C1 are subtractedtherefrom, in accordance with the following formula:Modified TSFCS2=TSFCS2+PTS1−TSFCS1

Given that the consecutive second main time stamps PTS1 have the sametime spacing between them as the consecutive content reproductionadvance main time stamps TSFCS1 respectively associated with thesesecond main time stamps PTS1, calculation of the content reproductionadvance secondary time stamps TSFCS2 may utilize any of the contentreproduction advance main time stamps TSFCS1 and the second main timestamp PTS1 associated therewith.

In the FIG. 6 numerical example, for the main content reproductionadvance time stamp TSFCS15=80 ms, associated in C1 with the second stampPTS15=20000 ms, the content reproduction advance secondary time stampsTSFCS2 are modified in accordance with the following formula:

$\begin{matrix}{{{Modified}\mspace{14mu}{TSFCS}\; 2} = {{{TSFCS}\; 2} + {{PTS}\; 15} - {{TSFCS}\; 15}}} \\{= {{{TSFCS}\; 2} + {20000\mspace{14mu}{ms}} - {80\mspace{14mu}{ms}}}}\end{matrix}$

As indicated by the downward arrow in FIG. 6, the time stamp TSFCS2=110ms following the detected time stamp TSFCS1 is modified as follows:TSFCS2=110 ms+20000 ms−80 ms=20030 ms,and the time stamp TSFCS2=145 ms is modified as follows:TSFCS2=145 ms+20000 ms−80 ms=20065 ms,and so on.

The secondary content reproduction advance time stamps TSFCS2 of C2 aremodified before they are passed to the secondary decoder. To calculatethe modified secondary time stamps TSFCS2, the second stamp PTS1associated with TSFCS1 is detected by the main detector, with thecurrent last content reproduction advance main time stamp TSFCS1 in themain component C1 received, and the main time value V1 thereof isextracted from the detected main time stamp TSFCS1 and its value isextracted from the second time stamp PTS1.

The main component C1 and the secondary component C2 are then reproducedon the basis of these modified secondary content reproduction advancetime stamps TSFCS2 and the second time stamp PTS1, rather than on thebasis of the stamps TSFCS1 and TSFCS2 as previously.

In C2, the modified secondary content reproduction advance time stampsTSFCS2 retain the same reference time as the second stamps PTS1 of C1,but set back by PTS15−TSFCS15=19920 ms relative to the main contentstart time stamp TSFCS10 of the main component C1.

The situation is discussed below in which the content when broadcast inthe television signals is intentionally interrupted by an unwantedcontent that is not strictly speaking part of the required content andcannot be selected in advance by the user when selecting the requiredcontent, this unwanted content consisting of advertising, for example.

A first option, represented in FIG. 4, in which the brace and theshading indicate the unwanted content, is to take account of theunwanted content in the main component C1 and in the secondarycomponent:

-   -   by providing in the main component C1 unwanted content main time        stamps TSFCS11 referenced to TSFCS10 (as indicated by way of        example by TSFCS=6 and TSFCS=11), associated unwanted content        main samples S11, wanted content main time stamps TSFCS1        referenced to TSFCS10 (as indicated by way of example by        TSFCS=7, 8, 9, 10) and associated wanted content main samples        S1, following on from the TSFCS11 and S11; and    -   by providing in the secondary component C2 unwanted content        secondary time stamps TSFCS21 referenced to TSFCS20, associated        unwanted content secondary samples S21, wanted content secondary        time stamps TSFCS2 referenced to TSFCS20 and associated wanted        content main samples S2, following on from TSFCS21 and S21.

According to this first option, the unwanted content is reproduced tothe user in its entirety with the second component C2.

According to a second option, represented in FIG. 5, in which the braceand the shading designate the unwanted content, there are no unwantedcontent main time stamps TSFCS11, unwanted content secondary time stampsTSFCS21 or associated unwanted content secondary samples S21. Theunwanted content main samples S11 are inserted into the main componentC1 between a main wanted content interruption time stamp TSFCS13(associated with its main wanted sample S13) and a main wanted contentresumption time stamp TSFCS14 (associated with its main wanted sampleS14) following on from the main wanted content interruption time stampTSFCS13, as indicated by way of example by TSFCS=6 and TSFCS=7. The mainwanted content interruption time stamp TSFCS13 is synchronized in thesecond component S2 with a secondary wanted content time stamp TSFCS23associated with its secondary wanted content sample S23 and the mainwanted content resumption time stamp TSFCS14 is synchronized in thesecondary component S2 with a secondary wanted content time stampTSFCS24, which is associated with its secondary wanted content sampleS24 and follows on from the secondary wanted content time stamp TSFCS23.

Consequently, according to this second option, the secondary componentof the unwanted content is not reproduced for the user, but waits forresumption of the main component before resynchronizing the secondarycomponent thereto in TSFCS24, the S23 reproduction duration being thatset by S13 and S11. The secondary samples from S24 onwards are thereforeplaced in a buffer in the terminal T to await the response.

The method of the invention is implemented in the terminal by anyappropriate means, for example a receiver module visibly added to theterminal itself and taking the form of a unit that the user can connectto the terminal, or a receiver module incorporated into the terminal andinvisible from the outside. This receiver terminal or module isimplemented using any electronic or data processing means appropriatelyprogrammed to execute the reception method. Accordingly, when the dataprocessing program installed in the receiver module is executed thereby,the usual functioning thereof, consisting in reproducing televisionsignals, is modified by virtue of the fact that the main component C1and the secondary component C2 are precisely synchronized forreproduction, which is particularly beneficial when the secondarycomponent C2 has a content linked to the main component C1, for examplewhen the main component C2 is speech in a language other than that ofthe soundtrack accompanying the main component C1 in the televisionsignals.

There is shown below data describing an audiovisual content inaccordance with the specifications of the TV Anytime forum(www.tv-anytime.org), after specifying the description of thesingle-network broadcasting of audiovisual contents:

<complexType name=“BroadcastEventType”>  <complexContent>   <extensionbase=“tva:ScheduleEventType”>    <attribute name=“serviceIDRef”type=“tva:TVAIDRefType”   use=“optional”/>    <attributeGroupref=“tva:fragmentIdentification”/>   </extension>  </complexContent></complexType> <complexType name=“ScheduleEventType”>  <complexContent>  <extension base=“tva:ProgramLocationType”>    <sequence>     <elementname=“PublishedStartTime” type=“dateTime”    minOccurs=“0”/>    <element name=“PublishedEndTime” type=“dateTime”    minOccurs=“0”/>    <element name=“PublishedDuration” type=“duration”    minOccurs=“0”/>    <element name=“Live” type=“tva:FlagType” minOccurs=“0”/>    <element name=“Repeat” type=“tva:FlagType”     minOccurs=“0”/>     <element name=“FirstShowing” type=“tva:FlagType”    minOccurs=“0”/>    <element name=“LastShowing” type=“tva:FlagType”    minOccurs=“0”/>    <element name=“Free” type=“tva:FlagType” minOccurs=“0”/>   </sequence>   </extension>  </complexContent> </complexType> <complexType name=“ProgramLocationType” abstract=“true”>   <sequence>  <element name=“Program” type=“tva:CRIDRefType”/>   <elementname=“ProgramURL” type=“anyURI” minOccurs=“0”/>   <elementname=“InstanceMetadataId”   type=“tva:InstanceMetadataIdType”minOccurs=“0”/>   <element name=“InstanceDescription”  type=“tva:InstanceDescriptionType” minOccurs=“0”/>  </sequence></complexType>

The following is an example of TV Anytime data describing thebroadcasting of an audiovisual content:

<BroadcastEvent serviceIDRef = “hbc100022311”>  <Programcrid=“crid://hbc.com/foxes/episode11”/> <ProgramURL>dvb://1.4ee2.3f5/</ProgramURL> <PublishedStartTime>2001-04- 07T19:00:00.00+01:00</PublishedStartTime> <PublishedDuration>PT6H</PublishedDuration>  <Live value=“false”/> <Repeat value=“true”/>  <FirstShowing value=“false”/>  <LastShowingvalue=“false”/>  <Free value=“false”/> </BroadcastEvent>    <Programcrid=“crid://hbc.com/foxes/episode11”/> identifies the audiovisualcontent.    <ProgramURL>dvb://1.4ee2.3f5/</ ProgramURL> identifies thebroadcast channel.   <PublishedStartTime>2001-04-07T19:00:00.00+01:00</PublishedStartTime> indicates the broadcast time.

The invention expands the definition of the element <ProgramURL> toallow the designation of a plurality of components that are availableseparately. The following are added:

-   -   the secondary component type: for example audio, subtitle, video        (for example TC2 a, TC2 b in the foregoing description with        reference to FIG. 1),    -   the secondary component language: for example French, English,        etc. (for example LC2 a, LC2 b in the foregoing description with        reference to FIG. 1),    -   the address at which the secondary component can be acquired,        which can be a multicast address, http URL or FTP URL, a DVB        channel, etc. (ADa, ADb in the foregoing description with        reference to FIG. 1).

The TV Anytime description data as modified in accordance with theinvention is as represented below, for example, with the elements addedor modified by the invention underlined.

<complexType name=“ProgramLocationType” abstract=“true”>  <sequence>  <element name=“Program” type=“tva:CRIDRefType”/>   <elementname=“ProgramURL” type=“ProgramURLType” minOccurs=“0”     maxOccurs=“unbounded”/>   <element name=“InstanceMetadataId”  type=“tva:InstanceMetadataIdType” minOccurs=“0”/>   <elementname=“InstanceDescription”   type=“tva:InstanceDescriptionType”minOccurs=“0”/>  </sequence> </complexType> <complexTypename=“ProgramURLType”>  <complexContent>   <extension base=“anyURI”>   <attribute name=“type” type=“ComponentType”   use=“optional”/>   <attribute name=“language” type=“mpeg7:ExtendedLanguageType”  use=“optional”/>   </extension>  </complexContent> </complexType><simpleType name=“ComponentType”>  <restriction base=“string”>  <enumeration value=“Audio”/>   <enumeration value=“Video”/>  <enumeration value=“ClosedCaptions”/>  </restriction> </simpleType>

For example, the description data is as shown below in the case of amain component made up of video, audio in French and subtitles inEnglish and a secondary component made up of audio in English acquiredin multicast mode via the Internet and subtitles in German acquired bydownloading via the Internet.

<BroadcastEvent serviceIDRef = “hbc100022311”>  <Programcrid=“crid://hbc.com/foxes/episode11”/> <ProgramURL>dvb://1.4ee2.3f5/</ProgramURL>  <ProgramURL type=“Audio”language=“en”>     igmp://234.2.2.2;audio 49170 RTP-AVP 0/</ProgramURL> <ProgramURL type=“Audio” language=“de”>http://www.channelFrance.com/titanic/de_audio.wav</ProgramURL> <ProgramURL type=“ClosedCaptions” language=“de”>rtsp://www.channelFrance.com/titanic/de/closedCaptions.st</ ProgramURL> <PublishedStartTime>2001-04- 07T19:00:00.00+01:00</PublishedStartTime> <PublishedDuration>PT6H</PublishedDuration>  <Live value=“false”/> <Repeat value=“true”/>  <FirstShowing value=“false”/>  <LastShowingvalue=“false”/>  <Free value=“false”/> </BroadcastEvent>

1. A method of receiving broadcast television signals on a multimediareceiver terminal, in which method a main component of televisionsignals broadcast via a first source is received in the multimediareceiver terminal, wherein main content reproduction advance time stampsreferenced to a predetermined reference time are inserted beforehandinto the main component to mark content reproduction advance; asecondary component for associating with the main component in order toreproduce for the user a coherent audiovisual content made up both ofthe main component and of the secondary component is acquired in themultimedia receiver terminal via a second source adapted to sendsecondary components, secondary content reproduction advance time stampsreferenced to said predetermined reference time being inserted into thesecondary component prior to reproduction in order to mark contentreproduction advance; and the received main component and the acquiredsecondary component are reproduced on the multimedia receiver terminalin compliance with the chronology of the secondary content reproductionadvance time stamps and the main content reproduction advance timestamps, to reproduce for the user a coherent audiovisual content made upboth of the main component and of the secondary component, and whereinthe main content reproduction advance time stamps each have a main valueof the time elapsed since said predetermined reference time; thesecondary content reproduction advance time stamps each have a secondaryvalue of the time elapsed since said predetermined reference time; andthe presence of a main content reproduction advance time stamp in thereceived main component is detected, the acquired secondary component issearched for a secondary content reproduction advance time stamp havinga secondary value immediately greater than the main value of thedetected main content reproduction advance time stamp, and reproductionof the acquired secondary component is started from the secondarycontent reproduction advance time stamp obtained by means of saidsearch, the secondary content reproduction advance time stamps beingspaced relative to the main content reproduction advance time stamps. 2.A method according to claim 1, wherein said predetermined reference timeis a published start time of reproduction of the content of the maincomponent.
 3. A method according to claim 1, wherein the main componentincludes, in addition to said main content reproduction advance timestamps referenced to said predetermined reference time, second main timestamps that are not referenced to said predetermined referenced time andare respectively associated with said main content reproduction advancetime stamps referenced to said predetermined referenced time; in thesecondary component, the secondary content reproduction advance timestamps are modified to have the same time reference as the second maintime stamps of the main component by adding to the secondary contentreproduction advance time stamps the time shift between the main contentreproduction advance time stamps referenced to said predeterminedreference time and the second main time stamps that are not referencedto said predetermined reference time and are respectively associatedwith said main content reproduction advance time stamps; and saidreproduction of the received main component and the acquired secondarycomponent on the multimedia receiver terminal is effected on the basisof the chronology of the modified secondary content reproduction advancetime stamps of the secondary component and the second main time stampsof the received main component, which are not referenced to saidpredetermined reference time.
 4. A method according to claim 1, whereinthe secondary content reproduction advance time stamps are present fromthe outset in the secondary component acquired from the second source inthe multimedia receiver terminal.
 5. A method according to claim 1,wherein the secondary content reproduction advance time stamps areinserted into the secondary component in the multimedia receiverterminal after acquisition in the multimedia receiver terminal from thesecond source.
 6. A method according to claim 1, wherein the step ofacquiring the secondary component includes storing the secondarycomponent received from the second source in a buffer of the multimediareceiver terminal and the step of reproducing on the multimedia receiverterminal (T) the received main component and the acquired secondarycomponent includes extracting the stored secondary component from thebuffer.
 7. A method according to claim 6, wherein the secondarycomponent is acquired by interrogating an address of the source ofsecondary components to be found in description data present with themain component in the received television signals followed bydownloading from the secondary component source to the multimediareceiver terminal.
 8. A method according to claim 6, wherein thesecondary component is acquired by interrogating an address of thesource of secondary components to be found in description data presentin metadata broadcast independently and received beforehand by theterminal or consulted beforehand by the terminal at a known address,followed by downloading from the secondary component source to themultimedia receiver terminal.
 9. A method according to claim 7, whereinthe description data includes for each identifier of a secondarycomponent the secondary component type selected from at least audio,subtitle and video, the secondary component language, and the respectiveaddress in the second source at which to obtain the secondary component.10. A method according to claim 6, wherein the secondary component isacquired from the second source with the aid of a manual search engineand downloaded from the second source to the multimedia receiverterminal.
 11. A method according to claim 6, wherein the secondarycomponent is acquired by sending the secondary component to themultimedia receiver terminal from the second source in multicast mode bythe secondary component source and storing the secondary component inthe buffer.
 12. A method according to claim 6, wherein the secondarycomponent is acquired by downloading the secondary component into thebuffer and reading the buffer in streaming mode.
 13. A method accordingto claim 1, wherein the main content reproduction advance time stampsinclude a main wanted content interruption time stamp and a main wantedcontent resumption time stamp after the main wanted content interruptiontime stamp, between which time stamps is a content unwanted in the maincomponent, and which are synchronized in the secondary componentrespectively with a first secondary wanted content time stamp and asecond secondary wanted content time stamp that is after the secondarywanted content time stamp, the secondary component between the firstsecondary wanted content time stamp and the second secondary wantedcontent time stamp corresponding to a wanted content other than theunwanted content of the main component.
 14. A computer-readable mediumstoring a program including code instructions which when executedperform at least the reception, acquisition and reproduction steps of amethod according to claim 1 when used in a terminal or module forreceiving broadcast television signals.
 15. A module for receivingbroadcast television signals, the module including means for receivingin a multimedia receiver terminal a main component of television signalsbroadcast via a first source and means for reproducing an audiovisualcontent for the user based on the received main component, wherein themodule further includes means for acquiring from a second source asecondary component associated with the main component to reproduce forthe user a coherent audiovisual content made up both of the maincomponent and of the secondary component; means for automaticallycontrolling the reproduction means so that the reproduction meansreproduce the received main component and the acquired secondarycomponent in compliance with the chronology of the secondary contentreproduction advance time stamps, referenced to a predeterminedreference time and each having a secondary value of the time elapsedsince said predetermined reference time, and main content reproductionadvance time stamps, referenced to said predetermined reference time andeach having a main value of the time elapsed since said predeterminedreference time; and means for detecting the presence of a main contentreproduction advance time stamp in the received main component, forsearching, in the acquired secondary component, for a secondary contentreproduction advance time stamp having a secondary value immediatelygreater than the main value of the detected main content reproductionadvance time stamp and to start reproduction of the acquired secondarycomponent from the secondary content reproduction advance time stampobtained by said search, the secondary content reproduction advance timestamps being spaced relative to the main content reproduction advancetime stamps.
 16. A receiver of broadcast television signals, thereceiver including means for receiving in a multimedia receiver terminala main component of television signals broadcast via a first source andmeans for reproducing an audiovisual content for the user based on thereceived main component, wherein the receiver further includes means foracquiring from a second source said secondary component associated withthe main component to reproduce for the user a coherent audiovisualcontent made up both of the main component and of the secondarycomponent; means for automatically controlling the reproduction means sothat the reproduction means reproduce the received main component andthe acquired secondary component in compliance with the chronology ofsecondary content reproduction advance time stamps, referenced to apredetermined reference time and each having a secondary value of thetime elapsed since said predetermined reference time, and main contentreproduction advance time stamps, referenced to said predeterminedreference time and each having a main value of the time elapsed sincesaid predetermined reference time; and means for detecting the presenceof a main content reproduction advance time stamp in the received maincomponent, for searching, in the acquired secondary component, for asecondary content reproduction advance time stamp having a secondaryvalue immediately greater than the main value of the detected maincontent reproduction advance time stamp and to start reproduction of theacquired secondary component from the secondary content reproductionadvance time stamp obtained by said search, the secondary contentreproduction advance time stamps being spaced relative to the maincontent reproduction advance time stamps.
 17. A television signalbroadcasting system including a first source of a broadcast maincomponent of television signals intended for a multimedia receiverterminal, the television signal broadcasting system further includingmeans for inserting into the main component main content reproductionadvance time stamps referenced to a predetermined reference time andeach having a main value of the time elapsed since said predeterminedreference time; a second source adapted to send a secondary component inwhich is inserted, before restitution, secondary content reproductionadvance time stamps referenced to said predetermined reference time andeach having a secondary value of the time elapsed since saidpredetermined reference time, the secondary content reproduction advancetime stamps being spaced relative to the main content reproductionadvance time stamps, said secondary component being intended to beacquired in a multimedia receiver terminal and to be associated with themain component to reproduce for the user a coherent audiovisual contentmade up both of the main component and of the secondary component; themain component and the secondary component being viewed on themultimedia receiver terminal in compliance with the chronology of thesecondary content reproduction advance time stamps and the main contentreproduction advance time stamps, said chronology including detectingthe presence of a main content reproduction advance time stamp in themain component, for searching, in the secondary component, for asecondary content reproduction advance time stamp having a secondaryvalue immediately greater than the main value of the detected maincontent reproduction advance time stamp and to start reproduction of thesecondary component from the secondary content reproduction advance timestamp obtained by said search.
 18. The television signal broadcastingsystem according to claim 17, further comprising: means for insertinginto the secondary component said secondary content reproduction advancetime stamps.